Project 10073 Record Card and Associated Correspondence — 25 April 1958

This document collection details a UFO sighting reported on 25 April 1958 by two pilots from the 413th Fighter Day Wing, George Air Force Base. The pilots, flying F-100C aircraft, were investigating a 'Sky Hook' weather balloon at approximately 45,000 feet when they observed a white, circular object. The object, described as being the size of a pea at arm's length, was estimated to be at an altitude of 150,000 feet, significantly above the balloon. The object was observed for 4-5 seconds, during which it performed a 180-degree turn and streaked toward the Pacific Ocean on a south-west heading. The incident occurred between Fresno and Merced, California, at 1725 Zulu time. The report was processed under Project 10073. Following the report, the Air Technical Intelligence Center (ATIC) initiated an inquiry to determine if any classified operations could account for the sighting. The investigation concluded that a U-2 aircraft, operating on a classified project from the Air Force Flight Test Center (AFFTC), was in the general area at the time of the sighting. The official assessment suggests that the pilots observed the U-2 aircraft, which performed a turn in the vicinity of the weather balloon. The report notes that both pilots were considered reliable and had excellent reputations for veracity. The documentation includes various message forms and record cards confirming the details of the event and the subsequent identification of the U-2 aircraft as the source of the sighting.